I've been using Lync 2013 in the last 12 months, and I love the product.

After applying KB2863908 some computers cannot log into Lync anymore. It gives the message "The server is temporarily unavailable..." This of course is a major problem.

I found  that I have this problem only for the computers (Windows 7 and Windows 8.1) that are not in the same domain as the Lync server. That is the computers that are in the domain they work fine as usual. The WORKGROUP and other domain computers have the problem.  Removing the patch fixes the problem, but I need a better solution.

Any ideas anyone?